Calc Word problem

Can someone please help me out.

Suppose a car is moving along straight road and distanct traveled t hours after starting from rest is given by f (t) = 2t^2+60t. Find the avg velocity of the car over the time intervals (0,2) and (1,2). Find the instanteaneous velocity at t = 1 and t = 2.

Can someone explain hte process of how to solve this? Using the method equations of

The instantaneous velocity is the gradient of a line that joins any point to another point extremely close to it. So for any point , you can say that a point close to it is , and the gradient would be .

So in your question, to evaluate the instantaneous velocity at , you know that on the curve, when . A point close to this would be , so .